示例#1
0
// UnmarshalBinary unmarshals the contents of a byte slice into an Attribute.
func (a *Attribute) UnmarshalBinary(b []byte) error {
	if len(b) < nlaHeaderLen {
		return errInvalidAttribute
	}

	a.Length = nlenc.Uint16(b[0:2])
	a.Type = nlenc.Uint16(b[2:4])

	if nlaAlign(int(a.Length)) > len(b) {
		return errInvalidAttribute
	}

	switch {
	// No length, no data
	case a.Length == 0:
		a.Data = make([]byte, 0)
	// Not enough length for any data
	case a.Length < 4:
		return errInvalidAttribute
	// Data present
	case a.Length >= 4:
		a.Data = make([]byte, len(b[4:a.Length]))
		copy(a.Data, b[4:a.Length])
	}

	return nil
}
示例#2
0
// parseAttributes parses netlink attributes into a Family's fields.
func (f *Family) parseAttributes(attrs []netlink.Attribute) error {
	for _, a := range attrs {
		switch a.Type {
		case attrFamilyID:
			f.ID = nlenc.Uint16(a.Data)
		case attrFamilyName:
			f.Name = nlenc.String(a.Data)
		case attrVersion:
			v := nlenc.Uint32(a.Data)
			if v > math.MaxUint8 {
				return errInvalidFamilyVersion
			}

			f.Version = uint8(v)
		case attrMulticastGroups:
			groups, err := parseMulticastGroups(a.Data)
			if err != nil {
				return err
			}

			f.Groups = groups
		}
	}

	return nil
}
示例#3
0
// parseRateInfo parses a rateInfo from netlink attributes.
func parseRateInfo(b []byte) (*rateInfo, error) {
	attrs, err := netlink.UnmarshalAttributes(b)
	if err != nil {
		return nil, err
	}

	var info rateInfo
	for _, a := range attrs {
		switch a.Type {
		case nl80211.RateInfoBitrate32:
			info.Bitrate = int(nlenc.Uint32(a.Data))
		}

		// Only use 16-bit counters if the 32-bit counters are not present.
		// If the 32-bit counters appear later in the slice, they will overwrite
		// these values.
		if info.Bitrate == 0 && a.Type == nl80211.RateInfoBitrate {
			info.Bitrate = int(nlenc.Uint16(a.Data))
		}
	}

	// Scale bitrate to bits/second as base unit instead of 100kbits/second.
	// * @NL80211_RATE_INFO_BITRATE: total bitrate (u16, 100kbit/s)
	info.Bitrate *= 100 * 1000

	return &info, nil
}
示例#4
0
// UnmarshalBinary unmarshals the contents of a byte slice into a Message.
func (m *Message) UnmarshalBinary(b []byte) error {
	if len(b) < nlmsgHeaderLen {
		return errShortMessage
	}
	if len(b) != nlmsgAlign(len(b)) {
		return errUnalignedMessage
	}

	// Don't allow misleading length
	m.Header.Length = nlenc.Uint32(b[0:4])
	if int(m.Header.Length) != len(b) {
		return errShortMessage
	}

	m.Header.Type = HeaderType(nlenc.Uint16(b[4:6]))
	m.Header.Flags = HeaderFlags(nlenc.Uint16(b[6:8]))
	m.Header.Sequence = nlenc.Uint32(b[8:12])
	m.Header.PID = nlenc.Uint32(b[12:16])
	m.Data = b[16:]

	return nil
}